Cooper Discoverer AT3s

By Glen Torrens, 31 Jul 2014Wheels & Tyres

In September 2011 I wrote of the first 15,000km with my new set of LT245/70/16 Cooper Discoverer AT3s under my 2005 Toyota Hilux. At that time, I related my overall happiness with the low noise levels and excellent grip of the then-new all-terrain tyres (designed with input from testing in Australia). I remember being disappointed in myself for not giving them the best start in life by neglecting regular tyre rotations at 5000km and 10,000km.

That was more than two years ago, and a few weeks before Christmas 2013, somewhere on the freeway between Sydney and Newcastle, those Coopers ticked over 100,000km. That’s been a remarkable life under my camper-equipped Hilux, especially when you consider it weighs 2.4 tonnes standing still and its logbook shows it’s pulling a trailer of 900kg to 1100kg around 30 per cent of the time.

But there’s fine print to this situation – there hasn’t been much off-bitumen travel on these tyres, so they haven’t been subjected to the callous nature of rocks and flint on outback roads. Knowing this, and with past experience of tyres showing significant deterioration in a few days of remote area travel, I kept a close eye on the tread blocks during a High Country/Snowies trek in April 2012.

Hauling 2.5 tonnes up the steep terrain of Victoria’s Billygoat Bluff and Mt Blue Rag – plus hundreds of kilometres of fast gravel running between New South Wales’ Tumut and Jenolan Caves on the return trek – can fray the edges of the tread blocks on any tyre. But there was nothing more than a pinkie fingernail’s chunk of damage to one tyre.

Since then, they’ve done a lap of Moreton Island, helped drag a race car half-way across Oz to Lake Gairdner (plus to other destinations as diverse as Grafton and Gippsland) and sweated in Sydney’s summer peak-hour traffic. Adding to this successful run is the fact I am careful with tyre pressures – 35 up front and 40 in the rear for my part-time 4WD Hilux, 15 on the beach and an extra five in the bum when towing, and I service and rotate the tyres often.

Yes, my non-rotation of the tyres for their first 15,000km came back to haunt me later – the tyre that started its life on the front left will carry this extra wear for the remainder of its life. Tyre-swapping allowed this tyre to spend extra time away from the left front to even-out all four tyres’ wear patterns. This tyre is seeing out its last few thousand kilometres with its more-worn shoulder facing the diff on the driver’s side rear.

For a quiet yet capable all-round performer for later model 4WDs, I’m just about stunned with these AT3s. Top job.